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arXiv · hep-ph/9706541

Chi_1 and Polarisation Asymmetries for Quarkonia at High Orders in Non-relativistic QCD

Sourendu Gupta·Prakash Mathews
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Abstract

We study doubly polarised asymmetries of c-cbar and b-bbar mesons in hadro- and photo-production at low transverse momentum in non-relativistic QCD to high orders in the relative velocity of the pair, v. We give the complete set of expressions required for the asymmetries up to order v^9. The asymmetries in the production of eta_{c,b} states are a stable measure of the polarised gluon densities. The asymmetries for chi_{c,b}, J/psi, psi', and the various Upsilon states are stringent tests of the NRQCD scaling relations.

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Sourendu Gupta, Prakash Mathews. 1997-06-30. Chi_1 and Polarisation Asymmetries for Quarkonia at High Orders in Non-relativistic QCD. https://doi.org/10.1103/physrevd.56.7341

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